BLOOMINGTON — Hikers are being warned about thick muck across the bottom of a drained southern Indiana lake where some people have become stuck.

People have ventured out onto the lake bed of Griffy Lake on Bloomington's north side since its water was drained this fall for dam repairs.

Peter Kienle tells The Herald-Times that his wife, 10-year-old daughter and his daughter's friend sunk up to their knees during a hike on Sunday. Kienle says his daughter freed herself but he used a long stick to help pull the other two out.

Steve Cotter of the Bloomington parks department says other hikers have needed help to escape the muck, leading to the placement of warning signs around the lake. He says the muck can be two to three feet deep.